Copyright Statement

Abstract

Novel saccharide-based stationary phases were
developed by applying non-enzymatic browning (Maillard
Reaction) on aminopropyl silica material. During this
process, the reducing sugars glucose, lactose, maltose, and
cellobiose served as "ligand primers". The reaction cascade
using cellobiose resulted in an efficient chromatographic
material which further served as our model Chocolate
HILIC column. (Chocolate refers to the fact that these
phases are brownish.) In this way, an amine backbone was
introduced to facilitate convenient manipulation of selectivity
by additional attractive or repulsive ionic solute–
ligand interactions in addition to the typical HILIC
retention mechanism. In total, six different test sets and
five different mobile phase compositions were investigated,
allowing a comprehensive evaluation of the new polar
column. It became evident that, besides the so-called HILIC
retention mechanism based on partition phenomena, additional
adsorption mechanisms, including ionic interactions,
take place. Thus, the new column is another example of a
HILIC-type column characterized by mixed-modal retention
increments. The glucose-modified materials exhibited
the relative highest overall hydrophobicity of all grafted
Chocolate HILIC columns which enabled retention of
lipophilic analytes with high water content mobile phases.